Investigating the Effect of an Attack on a Distributed Database

After an attack on a database system, evaluation of damage must be performed as soon the attack is identified. Otherwise, the initial damage would spread to other parts of the database via valid transactions, consequently resulting in denial-of-service. Damage assessment in a distributed database system is a complicated task due to intricate transaction relationships among distributed sites. In these systems, when any sub-transaction reads a damaged data at any site, the entire transaction of which the sub-transaction is a part, is considered affected by the damage. Hence, the data items updated by that transaction irrespective of sites are also considered damaged. This research focuses on damage assessment procedure for distributed database systems and uses a two-pass algorithm to obtain the final list of affected data items. The advantages of this method are: (1) the process is fully distributed in the sense that every site would execute the same algorithm, (2) the amount of data to be exchanged between the sites is minimized to the list of affected items at each site instead of the entire log, and (3) the local damage assessors can be executed in parallel at their respective sites